Rfi shielded vent



0 United States Patent 1111 3,5

[72] Inventors William E. Ciecarelli 2,378,518 6/1945 Trost 98/121 York, Pennsylvania; FOREIGN PATENTS agma 542,117 12/1941 Great Britain 98/121 W 22:23: 11:22; 2:22:21 "3221 Filed June 18,!969 1. [45] Patented Dec. 8, 1970 Primary Examiner-Darrell L. Clay [73} Assignee Gichner Mobile Systems, Inc. A110meyC1arence A. OBrien and Harvey B. Jacobson a corporation of Pennsylvania [54] RFISHIELDED VENT v 3 Chums Dnwhg 7 ABSTRACT: A vent for use in a shelter unit for communica- [1.8. CL on equipment or the constructed to provide an 98/121 shield, a blackout louver, and a raintight louver while ad- [51] lnt.Cl. "05k 9/00 ini d exhausting air incorporating back-to-back otsarcll 1 honeycomb panels of conductive material secured together 5-4,98/ 2l, with conductive adhesive with the cells of the honeycomb panels being upwardly and inwardly inclined toward the junc- [56] cued ture between the panels with the cells having nonreflecting NIT STATES PATENTS surfaces with the panels being connected with the metallic 2,361,186 10/1944 Fishbein et a1 98/ 121x construction of the shelter for RF] shielding.

RF! SHIELDED VENT The present invention generally relates to an assembly installed in an opening in the peripheral wall of an enclosure and more particularly to such an assembly installed in the window opening of a shelter unit employed as a protective enclosure for various communication equipment and the like to provide effective attenuation for RF! protection while permitting airflow therethrough and substantially preventing light transmission and protecting against rain entering the shelter.

An object of the invention is to provide an insert for an opening such as a window opening or the like in a shelter unit constructed of a honeycomb panel of conductive material grounded to metallic components of the shelter unit such as a metallic skin to provide an effectively RF] shielded interior for the shelter unit.

Another object of the present invention is to provide a honeycomb panel comprising at least two back-to-back honeycomb panels having the cells therein arranged in angular relation with the cells in each panel inclining upwardly and inwardly to serve as an effective baffle against rainfall entering the shelter unit.

Still another object of the present invention is to provide a honeycomb panel in accordance with the preceding object in which the two panels are secured in back-to baclt relation by a conductive bonding material such as a conductive epoxy adhesive or bonding material to further increase the RF! shield characteristics of the panel.

Still another feature of the present invention is to provide a panel in accordance with the preceding objects in which the cells are provided with darkor nonreflective surfaces to substantially prevent transmission of light.

Yet another object of the present invention is to provide a window opening insert in the form of a honeycomb panel in accordance with the preceding objects which is relatively simple in construction, easy to install, effective for its particular purposes and relatively inexpensive to manufacture.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIG. 1 is a perspective view of a portion of a wall of a shelter unit illustrating theassemblyofthe present invention incorporated therein; K

H6. 2 is a vertical sectional view taken substantially upon a plane passing along section line 2-2. on an enlarged scale, illustrating the structural details of the present invention; and- FIG. 3 is a fragmental perspective view illustrating a portion of the honeycomb panel.

Referring now specifically tothe drawings, the peripheral wall of the shelter unit in which the RFI shielded vent of the present invention is installed is designated by the reference numeral and may be of any conventional construction and include an external metallic skin or panel 12 and an interior skin or surface 14 whichalso may be metallic or any other material with the two panels being spaced apart by honeycomb material, foam insulation material or the like. The particular construction of the shelter unit does not .form a part of the present invention except that the shelter unit has the interior thereof RF l shielded due to the metallic skin periphery encircling the enclosed interior of the shelter unit. The shelter unit wall 10 includes an opening therethrough designated by numeral 16 with a peripheral'interior frame member 18 of L shaped configuration being provided as a finish for the interior of the opening 16 and a T-shaped peripheral frame 20 engaging the outer edge of the opening with the inwardly extending flange 22 of the frame telescoping and overlapping with the outwardly extending flange of the inner frame 18 and secured thereto in any suitable manner to define an opening for venting air in relation to the enclosure.

lnstalled in the opening is a panel generally designated by the numeral 24 which includes two back-to-back honeycomb panels 26 and 28 each having a plurality of continuous cells or passages extending therethrough to define a honeycomb panel with the cells of each panel being inclined upwardly and inwardly as illustrated in FIG. 2 and being of relatively small cross-sectional dimension. For example, the cells may have a dimension of three sixteenths of an inch in diameter and each panel 26 and 28 may have a thickness of five-eighths inch although these dimensions may quite widely vary. The angle of inclination may also vary but generally should fall within the range of 10 to 45 from horizontal. The panels are constructed of conductive material such as cadmium-plated aluminum honeycomb material. The panels 26 and 28 are bonded together in back-to-back relation by a conductive adhesive 30 such as a conductive epoxy material or the like and the interior of the cells are painted or anodized a dull black or other dull nonreflective-dark color and due to the double angle of the dark or black surface, light transmission will be substantially prevented while the double-inclined angle permits airflow and baffles against rain. With the conductive panels 26 and 28 being conductively interconnected and conductively connected to the metal skin 12, an effective RFl shield will be provided. The panels 26 and 28 may be conductively connected to the shelter unit by a conductive channelshaped peripheral frame 32 that is mounted on the inwardly extending flange portion of the T-shaped frame 20 also of conductive material. Thus, the panel 24 which may be considered a filter serves to permit passage of air but substantially prevent passage of light and rain and protect the interior of the shelter unit during various adverse weather conditions and also provide an effective RFl shield and protection for the interior of the shelter unit.

A closure plate 34 is hingedly supported from its upper edge by a supporting hinge structure 36 also supported from the shelter unit with the periphery of the plate 34 having inwardly extending flanges 46 receiving a peripheral seal 48 therein with a retaining flange 50 being provided against the interior of the seal 48 to retain it in position with the free edge thereof projecting beyond the flanges 46 and 48 as illustrated in FIG. I for sealing engagement with the frame 20 in peripheral scaled relation to the opening 16 and to the filter panel 24. Suitable fastening devices may be provided for locking the plate 34 in closed position thus completely sealing the opening 16 and suitable prop means or other latch devices may be provided for retaining the sealing plate 34 in open condition to provide for passage of air. When passage of air is not desired nor required, the plate 34 may be pivoted to a position for completely sealing the opening in the enclosure or shelter unit.

While the filter panel has been illustrated in a window opening, it may be installed in any opening in the shelter unit. In addition, a removable open-celled foam plastic filter such as foamed urethane may be provided for the opening to remove dust and other impurities entering the shelter unit. The foam filter may be easily removed, cleaned and replaced and may be used in combination with this invention.

By installing the filter panel 24, its conductive character and the inclined construction of the cells and its conductive-connection with the metallic periphery of the shelter unit serves as an effective RF l protection. The interior black color provided on the double-angle cells substantially prevents light transmission through the panel while permitting airflow. The inclination of the cells also serves as a baffle against rain or other inclement weather conditions. The pressure drop across the filter panel will remain within satisfactory limits and the attenuations of RF and light will be effectively attenuated.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

We claim:

1. A panel assembly disposed in a vent opening in the conductive peripheral wall of a shielding enclosure comprising a conductive honeycomb panel assembly having a periphery closely received in the opening and conductively connected with the conductive peripheral wall, said honeycomb panel assembly including a pair of back-to-back honeycomb panels with each panel having a plurality of cells extending therethrough for enabling air passage, the cells in each panel being inclined upwardly and inwardly providing a doubleangle baffle against entry of rain, the inner ends of said cells being disposed in a horizontal plane above the horizontal plane in which the outer ends of the cells are disposed, said honeycomb panels being constructed of conductive material and being bonded together in back-to-back relation with a conductive bonding agent to provide a continuous RF! shielded interior in the shelter enclosure, the transverse dimension of the cells being substantially less than the length thereof, and the interior of the cells being provided with a dark, nonreflective surface to absorb light rays to substantially prevent passage oflight therethrough.

74v The s e as defined in claim 1 wherein each uvuv ybUllll) anel is constructed of cadmium-plated aluminum with the angle of inclination ol'the cells falling within a range of approximately to 45 from horizontal.

3. The structure as defined in claim 1 together with a closure plate for the vent opening-hinge means supporting the upper edge of the closure plate above the upper edge of the opening, said closure plate having spaced concentric flanges thereon, a continuous peripheral sealdisposed between the flanges with the outermost flange being around the periphery of the plate, said seal extendingbeyond the free edges of the flanges for engagement with the; peripheral wall peripherally of the opening for sealing the opening-and means mounting the honeycomb panel assembly in the opening, said means including a peripheral conductive channel on the honeycomb panel assembly with inturned flanges-engaging the opposed surfaces of the back to back panels, a pair of peripheral L- shaped conductive members having telescopingly overlapping flanges defining an opening receiving the honeycomb panel assembly and spaced parallel flanges conductively engaging the inner and outer surfaces of the peripheral wall, and a projecting flange extending peripherally inwardly of the opening defined by the telescoping flanges with the projecting flange being integral with one of the telescoping flanges and defining a peripheral surface conductively engaging an inturned flange on the peripheral channel on the honeycomb panel assembly. 

